Field of the Invention
The present disclosure relates to touch display field, and particularly to a graphene sensor and a method of fabricating the same and a touch-sensitive display device.
Description of the Related Art
Graphene is a flat film constructed by carbon atoms in hexagon-shaped honeycomb crystal lattice with sp2 hybridized orbit (i.e., one s orbit and two p orbits are hybridized), which is one kind of 2D material having a thickness of one carbon atomic monolayer, i.e., 0.335 nm. A monolayer graphene has a light transmission of 97.7%. That is, it has excellent properties such as a high light transmission, a non-reflection, an ultrahigh carrier mobility (2*105 cm2/Vsec), a high flexibility, a high mechanical strength (tensile strength of 10-20 GPa), a good chemical stability, and a high thermal conductivity. The graphene as a transparent conductive film may be used to fabricate an ultra-lightweight, ultra-thin, high light transmittance and flexible touch screen.
It is a trend to develop a touch screen that has a big size and a narrow frame and is ultra-lightweight and ultra-thin. It is required to fabricate a metal leading wire having a thin line width with a high etching precision, and produce a product with narrow/ultra-narrow frame rim meeting the requirements. However, an existing screen printing technique to directly form a leading wire by a conductive silver paste does not meet the requirement of producing a product with the narrow frame rim. In addition, although a technique of fabricating an ITO touch sensor by etching an Indium Tin Oxide (ITO) film and a metal leading wire through a lithographic approach is a well-known technology that may achieve a high etching precision and high efficiency, the ITO film may be damaged during etching a metal layer. If the ITO film is replaced by graphene, then the graphene film may be not influenced by the corrosion caused by an acid solution during etching the metal, when fabricating the graphene touch sensor and the metal leading wire by the lithography. However, when fabricating a patterned graphene layer by the conventional lithography, an alkaline developing solution and an alkaline stripping solution contact the graphene film and cause the electrical conductivity of the graphene film to be degraded.